Product Safety for Potters

Course full!

I’ll be running it again in September. There are still some places available on my Studio Health and Safety for Potters course.


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Product Safety for Potters




What is the course about?

This course tells you what you need to know to make work that is safe for the user. This covers glaze stability and food safety, and also considerations for all the other aspects of producing good, safe functional work.

What are the Dates?

22 September – 9 November 2021
Eight weekly sessions, every Wednesday
19:00 – 20:30 UK time

What will we cover?

All aspects of product safety are covered, giving you the underlying theory, the means to test pieces, how to improve the design, and the relevant standards and legislation.

A considerable proportion of the course covers making durable glazes, crazing, leaching and food safety. Attention is also given to all the items that may be used on the table or in the kitchen. Also producing pieces that are frost proof. And general considerations such as stability and waterproofness.

What will I achieve?

By the end of this course you should be able to…

  • Understand the concepts of hazards and risks
  • Understand glaze stability, how to test it and how to improve it using the UMF, limit formulae, Stull chart and other guidelines
  • Understand the mechanisms of glaze leaching in both alkaline (dishwasher) and acidic (food) environments
  • Understand which materials in glazes are potentially toxic, and how likely it is that a glaze will be toxic
  • Understand the effects of thermal stresses on clay and glazes, and how to design to minimise them
  • Understand the requirements to make pieces safe for the dishwasher, oven, microwave and freezer, and methods of testing their behaviour
  • Understand the mechanisms of frost damage to pots, and the design and material considerations in making frost proof pieces
  • Understand the level of waterproofness needed by different pieces, and how to test it
  • Assess whether a piece is sufficiently stable for its purpose
  • Understanding the issues in making electric lamps both safe and compliant with the regulations as easily as possible
  • Design candesticks and other pieces with an open flme
  • Understand the legislation and standards covering product safety and testing (UK, EU and USA)

What level is the course and do I need any particular skills?


For the glaze section, some knowledge of glaze chemistry would be an advantage.

How will I be taught, and will there be any work outside the class?

Primarily through the weekly online sessions, which are a lecture but you can also ask questions or get a discussion going. In addition, there is an online forum that you can use at any time during the course.

There will be suggestions of aspects of your studio to consider between sessions.

Are there any other costs? Is there anything I need to bring?

No advance preparation is needed.

You may want to test some of your work (which will get damaged in the process). This mostly uses standard studio and kitchen equipment, though the following are useful if available:

  • A pressure cooker
  • Methylene blue or a similar dark stain (5ml is plenty)
  • pH paper or a pH meter
  • 50g of soda ash
  • A digital probe thermometer reading from -20° to 250°C

What do you get?

  • Eight live lectures with questions and discussions, lasting about 90 minutes each week
  • Additional online course material, giving background info and greater depth
  • Dedicated online forum for discussion by all students on the course, that I check at least once a day
  • Downloadable PDFs of all presentations
  • Recordings of all lectures for later viewing
  • Premium level access to the Tech part of my web site, containing much more information, references etc.

Note that the forum, lecture recordings and premium level site access are included at no cost until 4 weeks after the end of the course. After that, comtinued access is available for the cost of buying me a coffee every month (US$3 a month).

Feedback from students

I found the course both informative and enjoyable. Tim has a wealth of knowledge and experience, and a natural ability to present a technical subject in a way that makes it accessible to non-specialist. Recommended!
Edinburgh, UK 

I am happy to recommend Tim’s online webinar on Product Safety as a great way to improve the quality of your pots. He covers all the aspects of making from design to clay bodies, glaze materials and firing schedules. Coming from an engineering and design background his approach is quite different to that of the average art college. Whether or not you have a scientific background, testing and experimenting will become a natural part of your designing and making. Ideal for potters producing functional pots ranging from domestic ware to garden pots, who aim to improve their product.
St Albans, UK